Interior Lighting Out with a Buzz?

[Dan66]

Hey everyone,

My interior lighting is out. Doesn't come on when the doors open or with the dial control on the dash. But the oddest part is the buzz that's accompanying the problem...

I decided to have a closer look at the problem last night after the kids were put to bed (it was already dark out). I found that when the rear seat overhead lights were in the "on" position, they would glow very, very dimly. So dim they would've never been seen in the daylight. But when they were in the "off" position I would get a loud buzzing sound from the cargo area. It's coming from the jack storage panel. When I close all four doors though, the buzzing stops. If I start the engine, the buzzing comes on and stays on until the truck is turned back off.

I replaced the battery and alternator about 18 months ago. And everything else electrical works fine: motor turns over quickly, headlights are bright, stereo is loud, etc.

Any ideas?

 

[Dan66]

Hey folks,

A little update to this one...

As many of you probably already know (I didn't until this), there is a small fusebox inside the jack storage panel beside the rear washer bottle. That's the source of my buzz.

I gave it the jiggle test and the buzzing eventually stopped. But I still have no interior lights. Not with opening the doors or clicking the brightness dial or even when clicking the upper console map lights. The two have to be related somehow as they both happened at the same time...

Again, the battery and alternator are very recent, but I cleaned the battery posts and connections as a precaution. No change, though.

Any suggestions from anyone?

 

[Tbars4]

...That short (buzzing), could have failed the switch...

 

[Dan66]

Okay – Part three to the saga:

All the fuses check out okay, including #27.

I discovered it's a relay in that rear fusebox by the washer fluid container that's the specific source of the buzz. Went to Advance and got a replacement and it did exactly the same thing. The Advance employee and I then decided it's the fusebox itself (that the relay plugs into) that's the culprit.

It's the relay that all the green wires go to. All the wires appear to be snug to the underside of the box, yet with the relay in place, it's buzzing away! Any fiddling with the green wires changes the pitch of the buzz, but won't eliminate it.

Perhaps I need to replace the entire fusebox (?) Don't have any idea what it's proper name is, though...

 

[Bill Kemp]

Check out the ground side of the relay box and make sure (w/test light) that its grounded.